In the washing method of a traditional washing machine, the washing medium is water, adding water and detergents into the washing machine for washing; after washing, discharging the sewage from the washing machine via dewatering function, and then adding clean water again for continuing the washing or rinsing process, finally discharging water after the washing is entirely finished. In this method, the water is simply discharged and then clean water is refilled, thus causes a large amount of water consumption. Meanwhile, lots of chemical substances which are harmful to the environment are contained in the washing liquid, and the washing process is time-consuming with large power consumption each time.
To overcome the shortcomings of the aforesaid traditional washing method, in the prior art, some washing machines use an organic solvent as the medium, for example, a dry cleaning machine, in which the organic solvent is recycled; after the completion of one washing process, the organic solvent containing dirt is collected into a container, disposed by filtration and distillation, and then put back into the washing tub to continue the washing process. Due to the high toxicity of the organic solvent and the relatively low safety factor of medium recycling by distillation, it is not suitable for household use.
There is another washing method using air in the prior art, such as CO2. In this method, the medium is required to achieve the phase changes between gas and liquid, that is, medium is used for washing in liquid phase and then recycled in gas phase. The method demands not only a highly airtight structure, but also a high pressure for liquefying gas, which requires a high-pressure installation, so it is of low safety factor and complex process.
To overcome the shortcomings of the aforesaid washing methods, a washing method with the specially-made solid particles as the washing medium is provided, in which the dirt on clothes is adsorbed and then removed through the friction between the solid particles and clothes, so as to achieve the purpose of washing. The washing method can save over 80% water. Moreover, the solid particles as washing medium can be recycled and reused with a long service life, having no need to change, and being safe and environmentally friendly.
The current roller machines widely used usually comprise an inner tub and an outer tub, wherein, the outer tub is an enclosed structure which is provided with a water inlet and a water outlet; a plurality of openings allowing the water to enter the inner tub are arranged on the inner tub wall. During washing, the outer tub is fixed, while the inner tub rotates, where clothes are continuously lifted and dropped, imitating the most primitive washing theory of beating with a rod hammer. As solid particles cannot be separated, recycled and reused in washing machines of this structure, the aforesaid washing method using solid particles as the washing medium cannot be applied.